Not much going on today in the lab. Right now there’s not really much more I can do with the code until I get the results of some test runs that are going. Seeing as how the original run of Fgf took over five days to finish on a pretty beefy machine, I’m not holding my breath for it to finish anytime soon on the makeshift cluster of six halfway-decent machines. I would be shocked if it finished before I come in tomorrow morning.

There’s only one other machine I have access to that’s powerful enough to make running the code worthwhile, and right now I have it busy profiling the program, which will probably take another couple of hours. All the other machines I can use either have too little memory (this beast of a program needs at least 1.5 GB to process non-trivial inputs, and Sun’s JVM on x86 machines won’t let you go past 2 GB anyway) or too little processing power to run the program on anything but trivial inputs.

More annoyingly, all the inputs I have available fall into two main categories. The trivial ones can usually finish in under an hour, but lack the size and parallelism to really test the code and hit the corner cases and performance bottlenecks. The non-trivial ones are monstrous, like the aforementioned Fgf or the notorious 5507 (which still hasn’t gone through a successful run of the program, ever). In between, nothing. And at this point, the program seems to handle all the non-trivial inputs just fine.

I’ve already taken care of pretty much all the remaining little things to do in the code and squashed the few minor bugs that have popped up, but at this point I won’t know what else needs to be done until these test runs either finish or bomb out. I’m fairly confident now that they will work, but I really need to see some evidence of that fact. And there’s no telling how long that will take.

Plus, everyone else who’s usually in the lab, including the professor I’m working with, is off presenting their real-time Java stuff somewhere, so I’m the only one in the lab today.

So, if you’re looking for excitement today, this isn’t the place to find it.

6 Responses

Well, Paul, welcome to MY world. Now you know how I feel just about every single day. I never really have anything to do so I sit around most of the day. I sit at home, on the computer, during drivers ed, in the car, when reading, etc. Sad, isn’t it?

Sure, but I’m getting paid for it. Besides, once the profiling run finished I was able to start looking into the program’s hot spots, and in the process found a really nasty little bug that I probably wouldn’t have hit upon during testing. I think that’s the second bug I’ve found where I said to myself, “man, it would’ve taken me ages to find that one” after stumbling upon it while trying to do something else.

And Fgf is still going strong. Maybe this run will actually complete successfully in a reasonable time frame.

You jinxed it! Um, two hours before you posted. Aim that crazy time-travelling jinx power at someone else next time!

That’s what I get for complaining I don’t have enough to do. Now I get to track down some crazy bug or misguided parameter that caused five out of the six servers to pretty much stop doing anything about 24 hours into the computation. Won’t that be a fun one to track down, fix, and test. :-/